MYDCC
MYDCC
Last updated 3 March 2002. (Version 2 design for MYDCC are complete, Added a copy of the Version 2 Monitor program for download).
What's new in MYDCC Version 2;
1. Added a CV Ops mode programming.
There is nice Windows interface that is part of the MYDCC monitor program that allows the operator to read
and write any CV in Ops mode with additional screens/utilities to make things like CV29 and speed tables
easier to understand and program.
It's considerably more reliable that some of the other PC based CV utilities because timing does not rely on
Windows and the PC.
It uses the MYDCC controller for the timing critical events.
2. Part of the CV read write utility is the ability to save and load configuration files to and from disk.
You can also edit the configuration files with a simple DOS editor.
Pretty easy to figure out; each line in the file has the format of CV number, CV value (i.e. 2,34).
3. Modified the layout on the main board on the MYDCC to accommodate some of the new features.
4. Added a 5th level board for the CV Ack detector.
This means that there are two different connections to the MYDCC controller, one for the main track and one
for the Ops mode programming track.
When CV programming signals are sent to the programming track, the main track is disabled.
This means that locos that are left on the main track will not be reprogrammed.
So far I have a DCC controller, a project board that will convert the signals from a Digitrax DS44 or NCE SwitchIt to a pulsed signal with enough strength to switch a Kato switch or crossover and another board that will amplifiy the pulse from a Digitrax DS54 to a signal level that will switch a Kato single switch or crossover. The link to the first accessory decoder addon project (Acc1) is down at the bottom of this page. I have the other board built and working, I just don't have it very well documented yet and on the web page yet.
The MYDCC controllers are based on the Motorola 68HC11 microprocessor. It's an 8 bit processor that evolved out of the Motorola 6809 that was in the old Radio Shack Color Computers back in the late 70's. I use 32K of SRAM (fast volitile memory) and 32K of EEPROM (static memory that stays put when the power is off). The MYDCC software (which is free, I do this for grins) is downloaded to EEPROM via the RS-232 connection from a PC that has a free com port. It only has to be downloaded into the MYDCC controller once. After it's downloaded, the MYDCC controller will run by itself or it will optionally output info back to a PC for display status, provide audio and visual feedback to entered commands and play whatever .wav files you choose to associate with the different actions. The PC also provides the interface necessary to read/write the CVs.
I started out using a HandyBoard, a very well designed 68HC11 board that came out of a MIT robotics class. Right now I have two different designs. They are still based on the 68HC11 but use different degrees of "home brew". Both designs are functionaly the same and use the 68HC11D3 processor and include a booster.
The first design uses a small microprocessor board that uses a surface mount 68HC11.
The entire microprocessor board with memory is only 1" x 1.4".
It sets edgewise on a Radio Shack Proto board that measures 3"x4".
The RS board contains the booster and the RS232 communication to a PC.
Total cost to built is about $150 before adding the remotes.
Most of the cost is in the microprocessor board.
The microprocessor board is called a MicroStamp 11 (MS11) and is made by
The second design, MYDCC-D2, is built from scratch and costs less. It uses the CP (40 pin DIP) version of the 68HC11 and three RS proto boards to wire up all of the logic lines and memory. All of the wiring is done by soldering jumpers on the boards and stacking the boards on top of each other by plugging them together with male/female header connectors. The booster is on the fourth (top) level board that sets on top of the stack. The booster board is similar to the D1 design without the TechArts boards installed. Total cost to build computer controller with the booster is about $100.
Every thing is built on proto boards from my local Radio Shack. They are 3" by 4" (Radio Shack 276-168B). I use them because they're easy to work with. The booster uses International Rectifier FETs (IRF540) and HI/LOW side FET drivers (IR2101). These guys are rated for about 30 Amps. I'm not sure how much current this booster will handle but I've had 8 N-Gauge locos on it and the FETs are still only luke warm without adding head sinks. I'm sure there is a point someplace that heat sinks will have to be added, I just haven't found it yet. Plus, I don't know of any reason that two Boosters couldn't be stacked on top of each other running off of the same controller signal to double the current carrying capability.
There are two ways that the MYDCC controller gets its signal from an operator. Both involve the use of RCA universal remotes. The remote can be used as an IR transmitter just as it comes from the store for 5 to 10 dollars or it can be modified to a 433 MHz RF transmitter for another $10.
One of my goals was to stay with off the shelf parts. The FETs, FET drivers, DIP version of the HC11, and many of the small parts are available from DigiKey. Memory is pretty cheap from BG Micro. The MicroStamp11 computer board is from Technological Arts if you go that route. The RF transmitter/receiver boards are from the Radio Shack commercial catalog or web site. They can also be found on a few more web sites with a little searching. Many of the small parts; resistors, capacitors, DIP sockets can be found almost anyplace. I have parts lists for each of the designs with prices and sources for the harder to find items. These sources are only suggestions and availability and prices will no doubt change faster than I can keep up with.
The software for the MYDCC controller is all written in assembler and Visual Basic for the PC display portion. Since I'm not sure where I'm going with this yet I'm not going to put the source code out on the web. You can get the executable code for the PC here on the web page and the controller software just by emailing me for a copy. More than likely the source code will end up here some day since this is more of a hobby and I already have a real job.
As I already mentioned, there is a modification that can be done to convert the RCA remotes to RF. It's a lot easier than it sounds. In the Radio Shack commercial catalog or their web page, is a neat little transmitter/receiver pair that operate at 433Mhz. I've successfully fitted the transmitter into the RCU410 remote and the receiver onto the controller board. Works great. Now I can control the locos from anyplace in the house although I'm not really sure why I would want to. The real advantage to this is that now I don't have to point the IR remote at the receiver. The transmitter is embedded in the remote housing so there are no external changes. It can still be used as a regular IR remote if necessary. You select between IR and RF with a jumper on the booster board. There's more info in the build section below.
So, what does it do right now;
Quite a bit.
Control multiple locos with addresses of 1 to 9999 in 14, 28 or 128 speed step mode in forward and reverse.
Control up to 10 consists with up to 10 locos in each consist.
Turn Headlights on and off.
Turn F1-F4 on and off.
Control accessory decoders.
Allow multiple cabs (up to 6 so far), each with independent control of all 9999 locos with the IR or RF
receivers.
Display the current system status to a PC screen. (optional)
Play up to 99 separate .wav files on the PC with the remote.
Associate a .wav file with a command input.
Read/Write all CVs in Ops Mode.
All functions are controlled from a standard RCA type universal remote. After much trial and error and error, I've come up with what I think is a workable method of using the remotes for the cab control. The biggest problem that I had was figuring out what key presses worked with all of the different remote types. Some things are simply not implemented in all remote configurations. Volume controls have no meaning for VCRs. The record button has to be hit twice for some configurations but only on some remote units. The enter button is not implemented the same on different controllers, and on and on and on. The current configuration relies heavily on the number keypad and the VCR control keys. This really isn't a bad way to go since those keys are labeled with things like "go", "forward", "reverse", etc. Using the remote cab control is a lot like using a Hewlett Packard calculator with "reverse polish notation". You enter a number on the keypad followed by the command key for an action or command. Entering a command is usually just a few keystrokes. Full instructions are in the Operating Instructions of this web page.
There are several types of RCA universal remotes. This is a list of the ones that I've tried and found
to work:
SystemLink 5
RCU300W
RCU410W
I'm sure that there are more but I haven't tested them yet.
Multiple cab controls come from configuring the RCUxxx units to different types of VCR types;
2 different configurations of Sony, 2 configurations of RCA, Mitsubishi, and Tatung.
There may be more as I get a chance to try more configurations.
Some manufacturers configurations don't work very well for one reason or another so I stay away from them.
These configurations send out a continuous (as long as the button is held down) signal that can be reliably
recognized by the MYDCC software.
The reason that I wrote the PC companion program was so the operator has some sort of audio and visual feedback each time a button is pressed on the remote and to display the current status of the entire system. Since the remotes are really one way devices, there isn't a method at the remote to let the operator know that his key press or command was seen or understood by the controller; like an LCD display on the remote changing or a clicking key press. There is a small beeper on the controller that responds to each key press but when you get 3 people pushing buttons at the same time it gets confusing knowing if it was your key press or somebody else's that made the beeper beep. The PC companion program provides the feedback for multiple users. Each time a button is pressed, a color is flashed on the PC screen (different one for each of the six cab configurations) and a sound is played (again different for each cab). The sound is a wave file that you define. I use different loco whistles for each cab. You can define your own, in fact you have to. It kind of looks like a lot of the sound files that we can find out on the web may have a few legal attachments to them. So instead of me providing them and laying awake at night wondering if the .wav cops are going to break into my house and haul me off to jail, you can go download them. Now I can tell when the key has been read properly and what the current status of each loco is at a glance. I'll repeat it here again that the PC is not required except to download the program into the MS11. The PC display is an option.
Now I have a system where every remote unit (cab) acts the same and can control any one of the 9999 loco addresses and/or 10 consists without interfering with other operators. Loco addresses 1 - 127 use short addressing (the decoder responds to the address set in config variable #1) while any decoder addressed in the range of 128 -9999 must be configured for extended addressing.
So far I've run the following decoders on the MYDCC system with no problems;
Digitrax Mobil Decoders - DZ121, DN149K2, DN144K, DN146A
Lenz Mobil Decoders - LE077XF, LE062XF
Accessory Decoders - Digitrax DS54, NCE Switch-It
This web page is going to get updated in proportion to the interest anybody has in this design. If nobody really cares about it, then I'm just going to keep updating this page for my own documentation and keep still about it. If people get interested and want more info then I'll put more stuff out here.
Future Plans:
ToDo's:
1. -- Looking for suggestions.
I'm open to ideas. I know there are a lot of other functions to consider.
I have more information in the links and pics below.
WARNING -----------------
Here's the stuff that I have to add to this web page.
These build instructions and drawings work for me.
If you are planning on building or using this design I recommend that you have a basic understanding
of electronics and some level of skill for building things like this.
I don't make any claims that it's perfect and I can't take any responsibility for errors, yours or mine.